CF465A inc ARG

Sergey is testing a next-generation processor. Instead of bytes the processor works with memory cells consisting of $ n $ bits. These bits are numbered from $ 1 $ to $ n $ . An integer is stored in the cell in the following way: the least significant bit is stored in the first bit of the cell, the next significant bit is stored in the second bit, and so on; the most significant bit is stored in the $ n $ -th bit. Now Sergey wants to test the following instruction: "add $ 1 $ to the value of the cell". As a result of the instruction, the integer that is written in the cell must be increased by one; if some of the most significant bits of the resulting number do not fit into the cell, they must be discarded. Sergey wrote certain values ​​of the bits in the cell and is going to add one to its value. How many bits of the cell will change after the operation?

The first line contains a single integer $ n $ ( $ 1

Print a single integer — the number of bits in the cell which change their state after we add 1 to the cell.

In the first sample the cell ends up with value $ 0010 $ , in the second sample — with $ 0000 $ .